BU-214: Summary Table of Lead-based Batteries

The lead acid battery maintains a strong foothold as being rugged and reliable at a cost that is lower than most other chemistries. The global market of lead acid is still growing but other systems are making inroads. Lead acid works best for standby applications that require few deep-discharge cycles and the starter battery fits this duty well. Table 1 summarizes the characteristics of lead acid systems.


Starter (SLI)
Flooded, sealed

Flooded, sealed



Advanced Lead Carbon (ALC)


Many thin plates increase the surface for high current delivery, not spill-proof

Fewer thick plates give high capacity and durability, not spill-roof

Sulfuric acid is absorbed by a fine fiberglass mat; spill-proof

Electrolyte is suspended in silica type gel; spill-proof

Carbon anode improves charge and discharge performance

Nominal voltage



Full charge

2.45V at ambient, lower when hot

2.40V, or more

2.40V, or less


Float charge

2.30V at ambient, lower when hot

2.25–2.30V, sensitive to overcharge


Full discharge

1.75V, must be recharged to prevent sulfation


Specific Energy


20–30Wh/kg; some are higher

Charge rate

0.1–0.05C (16h charge time to get for full saturation)

2–4 times faster

Discharge rate

High momentary current

Continuous moderate current

Moderate to high current

High current

Cycle life
(full DoD)


150–200, longer if not discharged lower than 60% SoC

5–10 years for UPS

Better than regular lead acid


Flooded needs water;16 hour charge every 6 months to prevent sulfation

Maintenance-free; less prone to sulfation, no water can be added

Less prone to sulfation

Failure modes

Sulfation, shedding, depletion of active material, corrosion, mechanical



Standards to fit vehicle mount

Standards and unique sizes

30–100Ah typical; also unique sizes

Small and large sizes

Standards to fit vehicles, others


Lead is toxic, electrolyte is caustic

AGM, gel has less lead, electrolyte; avoid heat, use special charger



Oldest rechargeable battery in 1859 by Gaston Planté; coating of lead sheet  with lead oxides in 1880

Gates Energy, USA, in early 1970s

Sonnenschein, Germany, patent mid-1950s

New technology, experimentation, customization


SLI (starter, light, ignition) for vehicles

UPS, wheeled mobility

Military, aircraft, start-stop, racing, NASCAR, marine

UPS, wheeled mobility, busses, trucks, industry

Vehicles, military, energy storage


Well-suited for SLI. Low price; large temperature range

Ideal for UPS that needs few cycling

Big seller, cost effective, fast charging, high power but does not transfer heat as well as gel. Performs well when cold.

High ambient rating, high cycle count, less prone to sulfation, needs correct charge; costly. Tolerant at warm temperatures; low self-discharge.

Better charge acceptance for regenerative breaking; longer lasting

Table 1: Summary of most lead acid batteries. All readings are estimated averages at time of publication. More detail can be seen on:
BU-201: How does the Lead Acid Battery Work?
BU-201a: Absorbent Glass Mat (AGM)
BU-202: New Lead Acid Systems.

* AGM and Gel are VRLA (valve regulated lead acid) batteries. The electrolyte has been immobilized.

Last updated 2017-07-13

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Comments (3)

On July 26, 2016 at 5:38am
azhar 07 wrote:

how to calculate battery plate ah by its wight

for example in general local battery market 210 gram positive and 185 negative with 80 percent active material is called 15 ah automotive plate in lead acid battery

but in other part 160 gram positive and 150 gram negative plate is also called 15 ah
how it is wit this much wight difference

can any one answer my question ho to decide battery plate ah with its active material or lead wight

On September 7, 2016 at 11:00pm
gv wrote:

currently we are using the below batteries
>>          •  2 volt 200ah flooded lead acid tubular battery
>>          •  2 volt 1000ah flooded lead acid tubular battery
>>          •  12 volt 200ah flooded lead acid tubular battery

would like to know how to enhance the life of the battery, how to revive batteries. 

On November 12, 2016 at 6:07pm
Oscar Cardenas wrote:

Best regards.